KYIV, Ukraine (AP) — Ukraine says it sees possible room for compromise in talks with Russia. Meanwhile, Moscow’s forces have stepped up their bombardment of Kyiv, and an estimated 20,000 civilians have fled the desperately encircled city of Mariupol by way of a humanitarian corridor. The exodus marks the biggest evacuation yet of the bombarded seaport where the dead have had to be buried in mass graves. The fast-moving developments came on the 20th day of Russia’s invasion, as the number of Ukrainians fleeing the country eclipsed 3 million. A top Ukrainian negotiator, presidential adviser Mykhailo Podolyak, said after Tuesday’s talks via video with the Russians that there were “fundamental contradictions” between the sides, but that “there is certainly room for compromise.”